In satellite-based cellular communications, a plurality of satellites in orbit about the Earth are used to form communications cells upon the surface of the Earth. Cellular telephones and ground stations located within these cells communicate with each other through the satellites.
In a typical cellular communications system, the satellites form a dynamic constellation in a series of polar low-Earth orbits. Each satellite in the constellation typically generates a footprint of cells upon the surface of the Earth. These footprints tend to cluster or overlap, particularly at the poles. That is, because of the polar orbits, the footprints of adjacent satellites tend to have minimal overlap at the equator and maximal overlap near the poles.
A given satellite may form its footprint via an antenna array, where each antenna in the array generates a beam configured to form a single cell upon the surface of the Earth. If an antenna were to fail to produce a proper beam, the resultant cell would not be formed and there would be a communications hole within the footprint.
Various methods have been used to reassign the beams of other satellites to provide coverage for such a hole, i.e., to provide beam fill-in. Such methods have depended upon ground stations to update one-orbit tables within the satellites. These one-orbit tables work well as long as the hardware involved is operating properly. In the event of an antenna failure, however, the beam generated by that antenna may be out of service for up to a full orbit. This may represent a significant loss of communications and the revenue generated thereby, along with customer satisfaction.
What is needed is to dynamically monitor the operation of each antenna of each satellite in the network, and, in the event of a failure, provide dynamic beam fill-in for the failed antenna. In this manner, few communications holes would be allowed to exist for more than a few seconds, thus markedly increasing the reliability of the communications network, the revenue derived therefrom, and the customer satisfaction.